Search CAB Abstracts using your chosen terms, along with Boolean operators AND, OR and NOT (or the operators in the dropdown menus); the truncation symbol * gets variations such as other word endings and plural forms.
For example: (cotton or gossypium hirsutum) and (water or irrigat*)
The CAB Thesaurus will show what the indexing terms are for a topic. If you are having trouble finding 'it', check the thesaurus for other terms. There are also lists of corporate authors, 'subjects geographic" and 'subjects organisms'.
You may also limit searches with field tags, such as au: lastname author, or pb:publisher's name, like pb:CABI